Morphology and multigene phylogeny reveal three new species of Distoseptispora (Distoseptisporales, Distoseptisporaceae) on palms (Arecaceae) from peatswamp areas in southern Thailand.

Peatswamp forest is a unique habitat that supports high biodiversity, particularly fungal diversity. The current study collected submerged and dead plant parts from Eleiodoxaconferta, Eugeissonatristis and Licualapaludosa from a peatswamp forest in Narathiwat Province, Thailand. Morphological features coupled with multigene phylogenetic analyses of ITS, LSU, rpb2 and tef1-α sequence data identified our isolates as new Distoseptispora species (viz. D.arecacearumsp. nov., D.eleiodoxaesp. nov. and D.narathiwatensissp. nov.). Morphological descriptions, illustrations and notes are provided.

Burkholderia semiarida sp. nov. and Burkholderia sola sp. nov., two novel B. cepacia complex species causing onion sour skin.

Two putative novel Burkholderia cenocepacia lineages found in the semi-arid region of north-east Brazil causing onion sour skin were studied using genomic approaches to determine their taxonomic position. Four strains belonging to one novel lineage (CCRMBC16, CCRMBC33, CCRMBC74, and CCRMBC171) and one strain (CCRMBC51) belonging to another novel lineage had their whole genome sequenced to carry out taxogenomic analyses. The phylogenomic tree built using the type (strain) genome server (TYGS) clustered the strains CCRMBC16, CCRMBC33, CCRMBC74, and CCRMBC171 into the same clade, while grouped the strain CCRMBC51 separately. Average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) analysis showed values above 99.21 % and 93.2 %, respectively, among the strains CCRMBC16, CCRMBC33, CCRMBC74, and CCRMBC171, while ANI and dDDH values between these strains and the strain CCRMBC51 were below 94.49 % and 56.6 %, respectively. All these strains showed ANI and dDDH values below 94.78 % and 58.8 % concerning type strains of the B. cepacia complex (Bcc) species. The phylogenetic maximum likelihood tree constructed based on the multilocus sequence analysis of core genes (cMLSA) clustered the strains CCRMBC16, CCRMBC33, CCRMBC74, and CCRMBC171 and the strain CCRMBC51 in two exclusive clades, which did not cluster with any known species of the Bcc. Therefore, combined data from TYGS, ANI, dDDH, and cMLSA demonstrated that the strains represent two novel species of the Bcc, which we classified as Burkholderia semiarida sp. nov. and Burkholderia sola sp. nov., and proposed the strains CCRMBC74T (=IBSBF 3371 T = CBAS 905 T) and CCRMBC51T (=IBSBF3370T = CBAS 904 T) as type strains, respectively.

Isolation and Characterization of Bacteriophages Infecting Burkholderia glumae, the Major Causal Agent of Bacterial Panicle Blight in Rice.

Bacterial panicle blight (BPB), caused by Burkholderia glumae, is one of the most severe seed-borne bacterial diseases of rice in the world, which can decrease rice production by ≤75%. Nevertheless, there are few effective measures to manage this disease. In an attempt to develop an alternative management tool for BPB, we isolated and characterized phages from soil and water that are effective to lyse several strains of B. glumae. After tests of host ranges, the phages NBP1-1, NBP4-7, and NBP4-8 were selected for further comprehensive characterization, all of which could lyse B. glumae BGLa14-8 (phage sensitive) but not B. glumae 336gr-1 (phage insensitive). This result indicates that the phages killing B. glumae cells have specific host ranges at the strain level within the bacterial species. In the greenhouse condition of this study, foliar application of the phage NBP4-7 reduced the severity of BPB caused by B. glumae BGLa14-8 ≤62% but did not cause any significant effect on the infection by B. glumae 336gr-1. Electron microscopy and whole-genome sequencing were also performed to characterize the three selected phages. Transmission electron microscopy revealed that the selected phages belong to the family Myoviridae. Furthermore, whole-genome sequence analysis indicated that the three phages belong to a same species and are closely related to the Burkholderia phage KL3, a member of the Myoviridae family.

Complete Genome Sequence of Xanthomonas campestris pv. viticola Strain CCRMXCV 80 from Brazil.

Here, we report the complete 5.3-Mb genome sequence of Xanthomonas campestris pv. viticola (CCRMXCV 80), which causes grapevine (Vitis vinifera L.) bacterial canker. Genome data will improve our understanding of the strain's comparative genomics and epidemiology, and help to further define plant protection and quarantine procedures.